Do any jets from other carbs fit Thermoquads ?

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4bblfreak

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question- is there any interchange-ability between other makes/models of carburetor jets, and the jets in a Thermoquad ? I didn't spec it out yet myself, but does anyone already know what the thread size is on the 72-up TQ jets ? I have read on the net today using Holley jets in a TQ. I compared the 2 and Holley jets don't just thread right in, they'd have to be forced in, because the thread size on the Holley jets appears to be a tad finer pitch.
#2, the new Holley Demon Thermoquad knock-off carb, has interchangeable parts with the old TQ, namely the needle valves, floats, and accelerator pump shaft. Do the jets also interchange ?
any help appreciated, thanks.
 
If you put in primary Holley jets = Better get the right size the first time as
you will bugger up the threads (20 vs 24) in the phenolic.
I also think the perhaps the metering rod will not function right with the different
Holley jets because of different height.
I do have a large asst. of Thermoquad jets and a fixture to drill them that a mainly
used on the secondaries as they are unique.
 
In short, “no.”

IF! The bowl under the jet becomes unglued on both sides, you can tap the thread size and pitch in and re blue the bottoms back on. This I have not done—- yet…

As John has noted the height is of concern on the jets. Adjusting the tree height should do it. “should”

question- is there any interchange-ability between other makes/models of carburetor jets, and the jets in a Thermoquad ? I didn't spec it out yet myself, but does anyone already know what the thread size is on the 72-up TQ jets ? I have read on the net today using Holley jets in a TQ. I compared the 2 and Holley jets don't just thread right in, they'd have to be forced in, because the thread size on the Holley jets appears to be a tad finer pitch.
#2, the new Holley Demon Thermoquad knock-off carb, has interchangeable parts with the old TQ, namely the needle valves, floats, and accelerator pump shaft. Do the jets also interchange ?
any help appreciated, thanks.
 
In short, “no.”

IF! The bowl under the jet becomes unglued on both sides, you can tap the thread size and pitch in and re blue the bottoms back on. This I have not done—- yet…

As John has noted the height is of concern on the jets. Adjusting the tree height should do it. “should”
 
GTX John the NHRA SS class racer, said he taps his for Holley on both primary and secondary, carefully, in an older thread elsewhere on the net...you can tap coarse to fine using a bottom tap i.e. not as much lead taper in the tap, and perhaps let the small bowls under the jets in place... but...how long will it hold. my experience with rigging like that is...after a few jet changes it'll be stripped out altogether. the threads definitely will be compromised to some degree. there is a brass insert in the bowl with the threads in it, so it's not threading into the black plastic itself. my gut told me years ago, these carbs are cheap enough used in junkyards, scrap piles, sway meets, just buy a number of emission carbs post-'77 model years, and drill those jets in increments beyond the stock size. the jet/spring kits are still on Ebay $50 free shipping for 8 pairs of jet sizes and power piston, accelerator pump springs, which is a deal. thanks for the replies fellas...
 
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GTX John the NHRA SS class racer, said he taps his for Holley on both primary and secondary, carefully, in an older thread elsewhere on the net...you can tap coarse to fine using a bottom tap i.e. not as much lead taper in the tap, and perhaps let the small bowls under the jets in place... but...how long will it hold. my experience with rigging like that is...after a few jet changes it'll be stripped out altogether. the threads definitely will be compromised to some degree. there is a brass insert in the bowl with the threads in it, so it's not threading into the black plastic itself. my gut told me years ago, these carbs are cheap enough used in junkyards, scrap piles, sway meets, just buy a number of emission carbs post-'77 model years, and drill those jets in increments beyond the stock size. the jet/spring kits are still on Ebay $50 free shipping for 8 pairs of jet sizes and power piston, accelerator pump springs, which is a deal. thanks for the replies fellas...
Before I found strip kits I looked up all the thermoquad model numbers and their jettison. I bought a bunch of "junk" at swap meets but ended up with a good collection of rods and jets. You could also get a set of sized drill bits and drill out the common or useless sized ones, like the 125 secondary jets.
The stuff is out there you just need to look harder now.
 
that was my plan all along. I have a drill index, and spare carbs for parts.
 
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